In general, methods of bonding an object such as an electronic device to another object such as a base member, using a bonding metal are in widespread use. In particular, in the case of transferring an electronic device such as a semiconductor light emitting device after the manufacturing thereof, to another substrate, various bonding technologies using eutectic metals are employed in order to transfer the electronic device to a permanent substrate.
However, defects such as undesirable voids may be caused in a eutectic metal bonding layer formed through a reaction between bonding metals, such that bonding strength may be deteriorated. In particular, such defects may easily occur when a bonding surface is a non-flat surface, thereby significantly causing defective bonding between objects.
In addition, even after bonding the objects using a bonding metal, the objects may come separated from each other depending on a surface state of the bonding metal.